Table 3 Studies using a combination of carnitine and other nutrient supplementation to improve reproductive parameters

Effects of LC and CrNic on ovulation and fertilization rates in gilts

200 ppm LC + 200 ppb CrNic for 2 weeks prior to expected estrus

105 gilts

Positive controls were fed 11 lbs./day of complete diet (flushing)

Treatment group was fed 4 lbs./day of diet with/without various treatments

Increased ovulation and fertilization rate

[20]

Effects of dietary supplementation of LC and ascorbic acid in productive, reproductive, physiological and immunological performances of Golden Montazah aged breeder hens

100 and 200 mg LC/kg diet + 1 g ascorbic acid for 4 weeks

180 Golden Montazah hens + 18 cocks of 50 weeks old were randomly chosen. Birds were divided into 6 groups (each of 30 hens + 3 cocks), during the entire experimental period (from 50 to 70 weeks of age).

All groups fed diets of LC levels of 100 and 200 mg /kg diet alone and with 1 g ascorbic acid / kg diet were improved and recorded the best values of fertility and hatchability percentages.

This improvement was increased with increasing LC level compared with the hens fed 1 g ascorbic acid /kg diet alone and the control group at the end of the experimental period.

[87]

CoQ10 and LC co-treatment in ovulatory response in rabbits

10 mg/kg CoQ10 + 40 mg/kg LC for 21 days

New Zealand White female rabbits of 5.3 months old

Higher ovulate rate, number of follicles, corpus luteum and increased number of embryos

[85]

LC and vegetable oil supplementation in broiler breeder fertility

60 ppm (females),

500 ppm (males)

–

In 5th and 6th week, egg production is increased with more cholesterol in egg yolk

[44]

Dietary LC and choline chloride on reproductive indices in Holstein Dairy Cattle

50 g/day

From 1-week pre-calving to 4-weeks after parturition

Decreased SCC and improved other immune indices

[21]

Both LC and ALC supplementations on ovulation and oocyte quality in CD1 mice

0.4 mg LC and 0.12 mg ALC/mouse/day for 3 weeks

Female CD1 mice of 8 weeks old

Decreased percentage of oocyte degeneration with more developing oocytes

[47]

NAC and LC on prevention of oocyte damage in women with mild endometriosis

1.5 mM of NAC with 0.6 mg/mL LC in follicular fluid

In follicular fluid sample from infertile women with endometriosis aged less than 38 years who underwent ICSI and induced in bovine oocytes

LC and NAC combination prevented oocyte damage in mild endometriosis

[84]

Effect of oral antioxidant and LC combination on IVF-ICSI outcomes

Vitamin C (180 mg), vitamin E (30 mg), zinc (15 mg), selenium (50 mg), LC tartarate (400 mg), folic acid (200 μg) and CoQ₁₀ (40 mg) for 2 to 5 months at a daily dose of 2 capsules

Semen was taken for IVF and ICSI

• Enhanced semen quality

• Improved sperm DNA integrity, fertilization rate, pregnancy rate, implantation rate, embryo quality as well as blastocyst development rate

[88]

LC plus ALC on neuroendocrine control of hypothalamic functions in FHA

LC fumerate (863 mg), ALC (250 mg), vitamin-C (90 mg), N-acetyl cysteine (50 mg), vitamin E (30 mg), iron (7 mg), pantothenic acid (6 mg), zinc (5 mg), vitamin B6 (2 mg), copper (0.5 mg), β-carotene (4.8 mg), folic acid (200 μg), vitamin-D3 (5 μg), selenium (27.5 μg), vitamin B12 (2.5 μg)

27 patients (aged 26.5 ± 2 years) with FHA for the last 6 months were subdivided into 2 groups:

Group A (hypogonadotropic patients, plasma LH levels ≤3 mIU/ml, n = 15)

Group B (normogonadotropic patients, plasma LH levels > 3 mIU/ml, n = 12)

• Carnitine administration significantly increases LH secretion in patients

• Carnitine decreases cortisol and plasma amylase levels

[89]